Titanium and its metal alloys are examples of materials that currently are relatively expensive to produce. Titanium alloys can be used in forms such as castings, forgings, and sheets for preparing articles of manufacture. Titanium based materials can be formulated to provide a combination of good strength properties with relatively low weight. For example, titanium alloys are used in the manufacture of airplanes. But the usage of titanium alloys in automotive vehicles has been limited because of the cost of titanium compared to ferrous alloys and aluminum alloys with competitive properties.
Titanium-containing ores are beneficiated to obtain a suitable concentration of TiO2. In a Chloride Process the titanium dioxide (often the rutile crystal form) is chlorinated in a fluidized-bed reactor in the presence of coke (carbon) to produce titanium tetrachloride (TiCl4), a volatile liquid at room temperature. Traditionally, metallic titanium was produced in batch processes from the high temperature reduction of titanium tetrachloride (TiCl4) with sodium or magnesium metal. Pure metallic titanium (99.9%) was first prepared in 1910 by Matthew A. Hunter by heating TiCl4 with sodium in a steel bomb at 700-800° C. The first, and still the most widely used, process for producing titanium metal on an industrial scale is the Kroll Process. In the Kroll Process, magnesium at 800° C. to 900° C. is used as the reductant for TiCl4 vapor and magnesium chloride is produced as the byproduct. Both of these processes produce titanium sponge and necessitate repetitive energy intensive vacuum arc remelting steps for purification of the titanium. These processes can be used for the co-production of titanium and one or more another metals (an alloy) when the alloying constituent can be introduced in the form of a suitable chloride salt (or other suitable halide salt) that undergoes the sodium or magnesium reduction reaction with the titanium tetrachloride vapor. These high temperature and energy-consuming processes yield good quality titanium metal and metal alloys but, as stated, these titanium materials are too expensive for many applications such as in components for automotive vehicles.
The Armstrong/ITP process also uses alkali metals or alkaline earth metals to reduce metal halides in the production of metals. The Armstrong process can run at lower temperatures and can operate as a continuous process for producing a metal or metal alloy (such as titanium or titanium alloy) powder. However, the projected cost of the metal is still high, too high for many automotive applications.
A lower cost process is needed for the production of titanium and titanium alloys and compounds. It would be particularly beneficial if a lower cost process could be provided that had applicability to other metals and their alloys and compounds.